Yeah but like compiling large programs can take half an hour with an average CPU while making the system really sluggish. A developer working on large projects at their free-time could save a lot of time with a fast CPU
True, but with a slow CPU a developer working on large projects in their free time could just do something else while the computer works. There's always a book to read, exercise to do, household chores to knock out, kitties to cuddle, etc.